Folding knives typically include a handle and a blade that pivots relative to an end of the handle. When the blade is not being used, the blade is usually pivoted to a retracted position where the cutting edge of the blade is disposed in a slot in the handle. When the blade is being used, the blade is usually pivoted to an extended position where the cutting edge of the blade is exposed. Most folding knives also include a locking mechanism to lock the blade in the extended position. The locking mechanism primarily protects a user's fingers by preventing the unintentional retraction of the blade during use.
A typical locking mechanism includes a notch or flat surface near the pivot axis of the blade that is typically engaged by a bolt or catch to prevent the blade from pivoting. Unfortunately, due to the short distance typically provided between the pivot axis and the notch, a given torque, when applied to a blade that is locked, will create substantial forces on the locking mechanism thereby causing the mechanism to loosen, wear, or fail.
Furthermore, because the blade is typically fixed to the handle at only two points when locked (the pivot axis and the notch), the blade is susceptible to wobble and play when lateral or torsional forces are applied. As the mechanism wears, the blade becomes more susceptible to wobble and play.
In part because of the limitations described above, current folding knives are often too weak to withstand substantial force, and a rigid, one-piece knife must be used. However, one-piece knives require the use of a scabbard for safety, and the knife may not be converted to a more compact form for storage.
In view of the above, there is a need for improved folding knives and related methods that provide improved locking and better blade stability.